Fixes #5696: Overviews - On deletion of the 51th element it will show no entries

Co-authored-by: Benjamin Scharf <bs@zammad.com>
Co-authored-by: Rolf Schmidt <rs@zammad.com>

app/assets/javascripts/app/controllers/_application_controller/_generic_index.coffee

@@ -120,6 +120,11 @@ class App.ControllerGenericIndex extends App.Controller
 
       App[@genericObject][method](
         (collection, data) =>
+          maxPage = Math.max(1, Math.ceil(data.total_count / @pageData.pagerPerPage))
+          if @pageData.pagerSelected && @pageData.pagerSelected > maxPage
+            @pageData.pagerSelected = maxPage
+            return @navigate "#{@pageData.pagerBaseUrl}#{@pageData.pagerSelected}/#{encodeURIComponent(@searchQuery)}"
+
           @pageData.pagerTotalCount = data.total_count
           if data.total_count > @pageData.pagerPerPage || @searchQuery
             @dndCallback = undefined

spec/system/manage/overviews_spec.rb

@@ -413,4 +413,32 @@ RSpec.describe 'Manage > Overviews', type: :system do
       include_examples 'showing the error message if roles are empty'
     end
   end
+
+  describe 'Overviews: On deletion of the 51th element it will show no entries #5696', authenticated_as: :authenticate, searchindex: true do
+    def authenticate
+      Overview.destroy_all
+      create_list(:overview, 51)
+      searchindex_model_reload([Overview])
+
+      true
+    end
+
+    it 'redirects to the previous page' do
+      visit '/#manage/overviews'
+
+      first('.table-overview a', text: '2').click
+
+      expect(page).to have_current_path(%r{/#manage/overviews/2/}, url: true)
+      expect(page).to have_css('.table-overview tbody tr.item', count: 1)
+
+      # Delete the single item on the second page
+      find('.table-overview tbody .js-action').click
+      find('[data-table-action="delete"]').click
+
+      find('.modal-dialog .js-submit').click
+
+      expect(page).to have_current_path(%r{/#manage/overviews/1/}, url: true)
+      expect(page).to have_css('.table-overview tbody tr.item', count: 50)
+    end
+  end
 end